Electro-Harmonix Bad Stone Analog Six-Stage Phase Shifter Pedal

Electro-Harmonix Bad Stone: Vintage Six-Stage Phaser With a Manual Park Mode

The Electro-Harmonix Bad Stone is an analog phase shifter pedal that recreates the six-stage phasing of the classic 1970s original, with Rate, Feedback and a Manual Shift control. Where most phasers only sweep on their own, the Bad Stone adds a Manual mode that lets you stop the sweep and park it anywhere you like, opening static filter voices a standard phaser cannot reach. From a slow, oceanic swoosh under a clean chord to a fast, seasick warble on a funk riff, it covers the full range of vintage phase textures. It is the kind of pedal you switch on and instantly hear why phasing became the sound of an era.

How Six-Stage Analog Phase Shifting Works

A phaser splits your signal, shifts the phase of one copy through a series of all-pass filter stages, and recombines it so notches sweep up and down the frequency spectrum. Each pair of stages adds a notch, so the Bad Stone's six stages create three moving notches for a deeper, more resonant swirl than a simpler two or four-stage design. The Rate knob sets how fast those notches travel, from a barely-there drift to a rapid throb. Because the entire circuit is analog, the sweep stays smooth and musical, with the warm, liquid character that digital emulations chase.

Manual Mode and the Auto/Manual Toggle

The Auto/Manual toggle is what sets the Bad Stone apart from an ordinary phaser. In Auto mode the internal LFO sweeps the notches continuously at the Rate you set, the familiar hands-off phasing everyone knows. Flip to Manual and the sweep stops, letting the Manual Shift knob position the phase notches by hand for a fixed, cocked-wah-style filter tone. Guitarists use this to lock in a nasal, vocal midrange bite for a solo, or to create swells by turning the knob in real time.

Feedback: Setting the Depth and Intensity

The Feedback control feeds the phased signal back into the circuit, and it is the key to the Bad Stone's range. At low settings the phasing is gentle and understated, adding a subtle sense of motion without drawing attention to itself. As you raise Feedback, the notches deepen and the effect becomes more resonant and hollow, edging toward an almost oscillating, synth-like quality at the extreme. This single knob lets one pedal move from tasteful sparkle to full psychedelic drama.

Analog Voice for Guitar, Bass, Keys and Synth

The Bad Stone is voiced to handle more than just guitar, working cleanly with keyboards and synthesizers thanks to its analog design and generous headroom. On guitar it delivers the swirling rhythm textures of classic rock, funk and psychedelia; on bass it adds movement without swallowing the low end; on synths and electric piano it brings organic, hand-tuned motion to static patches. True bypass keeps your signal untouched when the pedal is off. With an 18mA current draw it sits easily on any pedalboard supply, or runs on a single included 9V battery.

Who the Bad Stone Is For

The Bad Stone is made for players chasing authentic vintage phaser tones, from swirling 1970s funk rhythms to spacey, psychedelic leads. Its Manual mode also makes it a favorite for anyone who wants fixed filter and cocked-wah voices without adding a separate wah pedal. Keyboardists and synth players gain an analog modulation that flatters organs, electric pianos and pads alike. If you want one phaser that covers both classic auto-sweep phasing and hands-on static filtering, the Bad Stone earns its place.